The atmosphere in Wolverhampton was tense and weary, as if the place was trying to emerge from a hangover. It was Wednesday. In twos and threes, fluorescent-jacketed police patrolled the city centre, keeping a careful eye on Queen Square, the compact public space where rioters had gathered the previous afternoon, under the watchful eye of a statue of Prince Albert.

In shop doorways, people taking fag breaks or sheltering from the drizzle talked about nothing else. By half past two, as shops closed early, the muted hubbub on the main streets had been joined by a new, unsettling sound: the low screech of electric screwdrivers, securing boards to shop windows, lest trouble should flare up again.

Outside a smashed and looted menswear shop called Le Monde, a 54-year-old glazier called Martin Frost was trying to improve on the defences that had been breached the day before. He scowled at the mention of looting. "I want to set up a vigilante group to calm the place down," he told me.

This time, disorder spread into seemingly unlikely places: Croydon, Ealing, Beckenham, Bromley, Gloucester. Such, perhaps, was the new model of disturbance facilitated by social media, and events based not so much on local factors as on sociology common across the UK: scores of people with nothing to lose and a tangle of grudges against authority.

There have been civil disturbances in Wolverhampton before: in 1981, 1987 and 1989, when a police raid on a pub sparked arson and looting. Ask anyone under 30 what it's like to like in Wolverhampton, and the same answers tend to come back: "boring", "nothing ever happens", "you've got to get out as soon as you can".

On Broad Street, I met Sham Sharma and his wife Sinita, standing in what remained of a computer shop called Sunitek, one of two they own in the city centre. They looked exhausted, and poleaxed by what had happened less than 24 hours before.

"While I was cashing up," Sham told me, "people smashed through, into the shop. Literally hundreds of them. They grabbed me by the neck: 'Where's the money?' I opened the till, and then I managed to get out." As he spoke, Sinita stood behind a broken counter, fighting back tears.

Just about every conversation I had in Wolverhampton reflected aspects of the riots that have become cliches at speed: this one pointed up the national sense that, at least initially, police merely stood and observed.

Sharma said there were riot police at the end of the street, but they told him they could not move until they had received orders. So it was that just about everything in the shop was ripped out and £300,000 of investment was destroyed.

He showed me smears of blood on the walls, and the forlorn remains of his stock: two or three crates full of plugboards and software CDs.

"In big cities, you might expect this, but not here," he said. "And they didn't look hungry or deprived. They were wearing designer clothes." He sighed. "Opportunist thugs. The UK's gone soft. Too many do-gooders."

Outside Beatties department store, a trio of young men – two British-Asian, one black – stopped and talked to me. "It's just a domino effect," said 20 year-old Ricco Jhara. "London does it, Birmingham does it, so Wolverhampton does it. And it's a load of dumb shit. Just to get clothes or a hat, you wreck a small business. Dumb, dumb shit."

Gangs, they said, were ever-present in local life, something proved by sporadic local headlines about such outfits as the Pendeford Crew and the Firetown Gang. Last year, Jamie Price, the son of the DJ and musician Goldie and a member of the Firetown Gang, was jailed for a murder bound up with the two gangs' rivalry.

"They're everywhere," said Jhara. "Everywhere. We have postcode wars, and all that. It's all about making money, man." I mentioned drugs, but no-one would be drawn any further.

For 10 more minutes, they spoke about looting, but it didn't take much persuasion to introduce another topic: their equally dim view of the police. "This is a rough, broken-down city," said Tobias Bailey, 19. "The police will pick out people, and bully and harass them." This year alone, he had been stopped and searched about 30 times. "They always say I match a description," he said. "Then it's, 'We stopped you, so we may as well search you.' "

Outside McDonald's, James Holmes, 23, explained what he knew of how the riot – the action, said everyone I spoke to, of a mixed crowd of black, white and Asian youths — had been organised. Early on Tuesday afternoon, he had been skateboarding in a nearby park, where people received word via Blackberry Messenger (BBM) that looting was in prospect at the Bentley Bridge retail park.

A group of 13- or 14-year-olds had been dispatched as an advance party, but had come back saying there were too many police.

"So I assume that's why they came here," he said. "You could feel the tension. And it didn't take much to ignite it." He laughed. "They even broke into the Jobcentre."

Close by, 14 year-old Zico Horton was sitting on his bike. He answered my questions in that taciturn, distracted, mildly amused way in which male adolescents talk to anyone significantly older. I wondered: did he know anyone who took part?

West Bromwich is 10 miles south-east of Wolverhampton, and six miles from central Birmingham. It has the feel of an afterthought: in London, it would sit at the end of a tube line.

The rate of youth unemployment here is 33%; the town centre has a pinched, sad ambience, and there are precious few of the usual high street names.

On Wednesday, I arrived at three o'clock, and instantly heard incessant chatter about what had happened the previous day: about six hours of trouble involving between 50 and 100 young people, who smashed windows with bricks, and tried to barricade High Street using a van and a Range Rover, which were set on fire.

Now, the only sign of any arson was a scorched patch of tarmac, outside an Indian Sweet Centre owned by Ranjit Singh-Dhillon. The two vehicles had been his. "Terrible," he said, quietly. "I've never seen anything happen like this in West Bromwich."

I walked down High Street, as far as the pink and black exterior of The Public, the "creative, community, cultural and business space" opened in 2009.

The local Labour MP Tom Watson, diverted from his campaign against News International, was pacing the pavements, having already entertained the shadow home secretary, Yvette Cooper.

His small-talk to local traders was self-explanatory: "Pretty grim, isn't it? Have things calmed down a bit?" As in Wolverhampton, everyone was closing early, pulling down shutters and staring anxiously up and down the street.

Watson introduced me to two local men, both owners of textile businesses, and regulars at the Guru Har Rai Sikh temple. "The hooligans were throwing bricks," said Jaginder Singh-Purewal, 58. "And the police were just standing there, not doing anything."

"Just staying back," added 60 year-old Parmjit Singh-Mann. "Either they were undermanned, or they'd been given commands to stay back."

"There were not enough police," said Singh-Purewal. "The same as everywhere you see on the TV."

They told me what they had done to defend the temple, after stones had been thrown at it: in the early hours of Wednesday, as many as 30 men had stood sentry outside, before groups of five or six worked in shifts. The rioters they had seen, they told me, had been "mixed, but mostly black".

In the shabby environs of Sandwell shopping centre, I managed a snatched conversation with six male teenagers – five black, one white — who admitted, between smirks, to having been in close proximity to Tuesday's trouble .They had the look of joiner-inners rather than instigators: callow, you might say; a bit daft, if you were being less generous.

Talking to them, I was reminded of scores of kids I can recall from school: the kind who would take no encouragement to go shoplifting, or render a classroom uncontrollable.

Contrary to stereotype, they were hardly feral: well turned-out, and fairly polite, they even issued the odd sentence that revealed traces of social conservatism. When I mentioned the issue of parenting, one voice shot back: "If you can't beat your children, they'll be naughty."

Besides an amusement arcade, the other shop that suffered serious damage was West Bromwich's branch of the big-box chain Staples. "When Staples was getting trashed," said a 16-year-old who called himself Critz, "the police were just standing there. Four riot vans; 20 or 30 police. It was like they wanted us to do Staples."

Why did people do it?

"Free shit," said a voice. "And fucking the system."

"You smash up the shops," said a boy who would only identify himself as Corey, "and you get free stuff. Everything's about money these days, innit?"

"If they're stopping EMA [Education Maintenance Allowance]," added another, "what do they want us to do?" Hearing this, I wondered whether this was a line cynically pinched from some talking head on the TV, and parroted back at me, but all six said they wanted to go to college – a music course was mentioned, with retakes of GCSEs – but in the absence of the EMA, they were now wondering whether it was worth it.

And from there, we plunged into the familiar topic of police harassment, and their claims to have extensive experience of it. "Here's my quote on that," said one voice. "If you're not white, you're not right."

When the photographer requested a picture, up went the hoods, and out came the black bandanas: we were now facing feral youth, straight out of central casting. They threw a few cliched shapes, and then dispersed, apparently rattled by the attention of the police.

The same kids collared us 10 minutes later: Corey, they said, had been arrested, after being approached by the police and refusing to take off his coat. We watched him being loaded into a van, while an officer squatted by its door, apparently filling in the requisite paperwork.

"People was running round with machetes yesterday," marvelled Critz. "The Feds did nothing. And he's just been arrested for not taking off his jacket."

We were standing outside The Goose pub. In front of us were a single police van, and six officers. A spread-out crowd congregated, seemingly waiting for something to happen.

Nothing did: on Wednesday and Thursday night, Wolverhampton and West Bromwich stayed quiet – decidedly tense, perhaps, but back to that pained model of existence, where life plods on, and the outside world takes no notice.